Escapement mechanism



Feb. 9, 1965 J. F. FAZIO 3,168,832

ESCAPEMENT MECHANISM Filed April 2, 1963 Fig, I

INVENTOR JOHN F. FAZIO the accompanying drawings and its scope r the appended claim.

United States Patent 3,168,832 ESCAPEMENT MECHANISM John F. Fazio, Philadelphia, Pa., assignor to the United The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to escapment mechanismssuch,

as constitute a part of the clockwork movement employed in mechanical time fuzes. It provides an improved escapement mechanism which isdistinguished from those heretofore available by the ease with which it is adjusted to compensate for variation in the size of the escapement wheel which forms a part of the mechanism.

Heretofore, the lever assembly of the escapement mechanism has been mounted in the clockwise movement in a predetermined position where there is a desired lock or depth of engagement between the escapment wheel and the pallets. No adjustment has been provided to compensate for any variation of the lock? due to manufacturing tolerances, methods of assembly or other factors. Under these conditions, the trial'of several escapement wheels or the bending of the escapement spring is frequently required to obtain an operable escapement mechanism. Neither of these expedients. is satisfactory; The trial method of selecting the escapement wheels involves too much time. 'The bend in the escapement spring is prone to change with time. The present invention avoids these difficulties by the provision of means whereby the fixed end of the escapement spring may be adjusted laterally until optimum operating conditions are realized.

The invention will be better understood from the 'following description when considered in connection with is indicated by Referring to the drawings:

FIG. 1 illustrates a clockwork which embodies the escapement mechanism of the invention,

FIG. 2 shows the escapement mechanism as utilized with a one-half hair spring, p

FIG. 3 depicts the escape mechanism as utilized with a full hair spring, and

FIG. 4 is an explanatory diagram relating to the adjustment of the pallets with respect to the escapenient gear. A

The clockwork of FIG. 1:includes a mainspring 10 which functions through a gear train 11-12-13-14-15 to drive an escapementwheel 16. This escapement wheel is anism including a pair of pallets 18 and-19 and the pallet lever 20 -21 on which theyare mounted. The pallet lever 20-'-21 is pivoted on a shaft 22 and this shaft is con-' nected to an escapement spring-23 one end portion of which is slidablyreceived by a slotted upstanding leg of support 24. This support is adjusted substantially longitudinally of spring 23 by a'screw 25 to regulate the operating frequency of the escapement mechanism.

FIG. 2'shows the escapement mechanism as utilized with a one-half escapement spring and FIG. 3 shows this mechanism as utilized with a full or complete escapement spring. In the modification of FIG. 2, the support 24 is not only adjustable by the screw 25 for regulating the operating frequency of the escapement mechanism but is also adjustable by a screw 26 for effecting the optimum depth of engagement between the escapement gear teeth and the escapement lever pallets. From FIG. 2, it can be seen that the support 24- is located in a slot 27 and that the force exerted by the screw 26 is opposed by a spring 23.

In the modification of FIG. 3, a separate support 29 and screw 30 are arranged to adjust the depth of engagement between the pallets and the teeth of the escapement gear. Thus the escapement assembly has the lever 20-21 fixed in the center of the spring 23, one end of the spring is slidably received by the support 24 and the other end of the spring is slidably received by the support 29;. Under these conditions, lateral adjustment of one end of the escapernent spring by the screw 36) causes the pallets to rotate varying the position of the spring as indicated by the divergent lines 31 of FIG. 4, and varying the depth of engagement between the pallets 18 and 19 and the teeth 32 of the escapement gear 16. This lateral adjustment has the important advantage, previously mentioned that it saves the time heretofore involved in selecting a work-v able escapement gear and avoids the use of an unreliable bent escapement spring. 7

As will be apparent to those skilled in the art, the above described adjustable supports of the escapement spring may assume various forms. For example, both motions may be imparted to one end of the spring illustrated in FIG. 3 or both motions may be imparted to both ends of this spring. In either case the same advantageous result is attained.-

I claim:

In an escapement mechanism, the combination of I a gear,

a lever fixed to a pivoted shaft and bearing a pair of pallets arranged to engage the teeth of said gear,

a support,

a spring having one portion fixed to said shaft and another portion longitudinally spaced from said one portion and slidably received by said support,

means'for adjusting said support laterally of said spring whereby the depth of engagement between said pallets may be adjusted to an optimum value, and

means for adjusting said support longitudinally of said springfor regulating the operating frequency of said .escapement mechanism.

References Citedby thejl lxaminer I 1 ii UNITED STATES PATENTS -1',s56,9o7 10/25 Bold 58- 109 X 7 2,968,186 '1/ 6 1 Jeanneret I 58 -116 X 

